Series boiler with superheater between boiler tubes



Oct. 18, 1932. D. s. JACOBUS 1,883,294

SERIES BOILER WITH SUPERHEATER BETWEEN BOILER TUBES 5 Sheets-SheetOriginal Filed April 16 191.8

\ lNV NTOR BY g wfiwq ATTORNEYG D DUUUU umnmumum mmm 06L 18,1932. [1 5,JACQBUS 1,883,294

SERIESL-BOILER WITH SUPERHEATER BETWEEN-BOILER TUBES Original FiledApril 16. 1918 3 Sheets-Sheet 2 UDELDEJD EIEJUDDUEI INVENTOR gyi/ w 49 JATTORN EYS Oct. 18, 1932. D. s. JACOBUS 1,833,294

SERIES "BOILER WIT SUPERHEATER BETWEEN BOILER TUBES Original Filed April16. 1918 3 Sheets-Sheet L;-

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)JFWENTOR BY W 6% FJM ATTORNEYS 77 Patented Oct. 18, 1932 UNITED STATESPATENT OFFICE.

DAVID S. IACOBUS, OF MONTCLAIR, NEW JERSEY, ASSIGNOR TO THE BABCOGK &WILCOX COMPANY, OF BAYONNE, NEW JERSEY, A CORPORATION 01 NEW JERSEYSERIES BOILER WITH SUPERHEATER BETWEEN BOILER TUBES Original applicationfiled April 16, 1918, Serial No. 228,827. Divided and this applicationfiled. September 19,

1928. Serial This is a division of my application Serial No. 228,827,filed April 16, 1918. The invention relates especially to the locationof the superheater in' a series boiler and will be understood from thedescription in, connection with the accompanying drawings in which Fig.1 is a diagrammatic sectional side elevation showing an illustrativeembodiment of the invention in a boiler that is stoker fired;

Fig. 2 is a similar view showing a modification with some of the partsomitted; and Fig. 3 is a similar view showing another modification ofthe invention in a boiler that is provided with oil burners.

In the preferred form of my invention, the

boiler comprises a series of boilerheader boxes to which tubes areconnected, the tubes being. preferably of U-form, extending upwardlyfrom the headers.

-A part of the tubes are economizer tubes, part of the tubes are boilertubes, and part of the tubes are superheater tubes for superheating thesteam after it'has been separated from the water with which it flowsthrough the boiler tubes. The superheater tubes are located between theboiler tubes in a pass for versely extending header boxes 2 is locatedalong the lower side of the flue 1 and U-tubes 3 extending upwardly fromthe'header boxes 2 connect the same. The header boxes 2 are preferablytransverse to the flow of the gas and are protected therefrom by therefractory bottom 4 of the furnace chamber or flue.

There is no definite line of division between the economizer portion ofthe boiler and the boiler itself. Variations in the rate of feed of theboiler, the temperature of the feed water,

used with boilers as the carrying of a small I amount of moisture by thesteam into the superheater is an ordinary occurrence.

In Fig. 1 the economizer portion A is made up of the tubes most remotefrom the source of heat which is indicated as a furnace 5 having a grate6. B indicates a portion of the boiler tubes that is the evaporatingsurface, and 0 represents the remainder of the boiler tubes which arenearest the source of heat. The superheater tubes S are located betweenthe portion B and the portion C of the boiler tubes. The off-take 7 forthe flue gases is shown at the right. Hottest gases flow over thehottest boilenheating surface and coldest gases over the coldest surfacethereby embodying the so-called counterflow principle. The feed waterenters the boiler through the pipe 8 leading into the rearmost headerbox of the economizer portion A. This water flows thence through theU-shaped tubes 3 and the successive boxes of the series toward thefurnace end, the water or the combined steam and water pass forwardlyinto the successive boxes 2 and tubes 3 to the header 9 which is theforemost header of the boiler tubes proper. with a regulated amount ofwater passes down through pipe 11 into a separating tank 12, the pipe 11preferably having a handcontrolled valve. A pipe 15 leads from the steamspace of the separator 12 to the rear header 16 of the superheater S1From the superheater headen16 the steam'iiows through the U-tubes of thesuperheater into the header 18 from which it flows through the outletpipe 19. By locating the superheater in this position, there is less daner of burning the superheater tubes than in oilers of the From thisheader 9 the steam sort where the hottest gases flow over thesuperheater tubes. The counterflow principle may be'retained both in theboiler portion and the superheater portion.

The water feed to the ecpnomizer and boiler is controlledin thefollowing manner: The separator tank 12 is shown as a horizontalcylinder or drum and the amount of feed water admitted to the boilerthrough the pipe 8 is regulated by a feed regulating device 20 ofwell-known construction so as to maintain approximately constant levelof water in the separator 12. The water from the separator passesthrough the valved pipe 21 to the feed tank 22, a coil 23rbeing used totransmit the heat from the water passing from the separator 12 into thefeed tank 22 and prevent loss of heat through the vapor escaping fromthe point where-the hotwater from the valve pipe 21 mixes with the waterin the feed tank. The feed regulating device 20 is operated in awell-known manner from the container 24 that is connected by tubes 25 tothe steam space and water space, respectively, of the separator 12 sothat the Water'level in the container 24 will vary in accordance withthe water level in the tank 12 and operate the regulator 20 in such amanner that the amount of water forced into the boiler'through the pipe8 by means of the pump 26 will increase when the level in the tank fallsand will decrease. when the level in the separator '12rises.

The frictional resistancemf the water and steam flowing through theseries boiler is a material factor and the pressure of the feed waterentering through the pipe 8 must be sufiiciently high to overcomethefrictional resistance of the flow. The'frictional resistance variesgreatly, increasing with the load and where a constant pressure ismaintained in the steam discharged from the boiler, the pressure of thefeed water entering into the pipe 8 must be correspondingly varied. Thesteam andwater from the portion 9 enter the separator 12 where the twoseparate and the steam passes up through the pipe 15 to the header box16 of the header and thence through the superheater and out through pipe19.

In the modification shown in Fig. 2 the parts are similar to those abovedescribed and the separating tank, feed pump, etc. have not been shown.In this modification, however,

being heated by a grate. The parts corresponding to the parts in theillustrative embodiments already described are marked with the samereference characters to which the subscript 3 is applied. The boilerportion is divided into two sections B and G with the superheater 8;,between them so that the hot gases from the furnace contact with theportion C of the boiler or evaporating tubes, thence pass over thesuperheater tubes S thence over the boiler tubes B and thence over theeconomizer tubes A before reaching the up-take 7 The oil burners 29 maybe spaced along the front of the furnace, part of which is broken awayin the drawings. Or a stoker or hand-fired grate may be used in this andthe other embodiments of the invention.

In the form shown in Fig. 3 the feed water passesthrough the pipe 8 tothe rear header box 2 and thence flows upwardly through the economizertubes A and thence downwardly to the header box 30. From this header boxthe water, then flows upwardly through the tubes 31 into the header 32.The headers 32 are at a slightly higher level than the headers 30 andthe tubes 31 are spaced alternately with reference to the downtake tubesleading into the header box 30. The succeeding arrangement is similar,the downflow tubes being spaced alternately with the uptake tubes ofeach box until the header 33 is reached. From this header the steam andwater flow through tubes 34 which have wider bends bridging thesuperheater tubes S and entering the header 35. From the header 35 thesteam and water flow progressively through the boiler tubes C andfinally enter the header 9 From this header the steam and water passthrough a series of pipe con nections 36 into a cross pipe 37. The wateris separated from the steam in this cross pipe and the water flowsthrough a number of small pipe connections 38 through the valveconnection 39 and to the tank 12 From the separating pipe 37 the steamfrom which the greater part, or all of the water, has been separatedpasses upwardly through the small, pipes 40 into the superheater header4:1. From this header the steam passes through superheater tubes intothe superheater header 42 from which it is taken away. The level ofwater in the tank 12 may be maintained in a manner already described inconnection with Fig. 1. The Water in the tank 12 may be led oif throughthe pipe 43 to a feed tank and recirculated as above described. A

blow-off connection 44 is provided for the of the invention, any ofthese special features may be used on any of the forms shown on eitherform of my invention. I v

The. changes in my invention result from overcoming a number of thedifliculties incident to series of boilers and the obtainingof thefeatures described therein. Utilizing of the frictional resistancethrough flow through the various sections, comprising the economizersection, the evaporating section, and the superheater section is animportant feature. In ordinary economizer practice the temperature ofthe water delivered by the economizer is kept below the steaming point,since if the water in the economizer reaches this point it will causethis water to belch over from the economizer.

This will at once cause a rise in the water level of the boiler and thefilm will naturally partly close the feed valve in the boiler to reducethe flow thereinto. Cutting down the flow of the feed water will causestill more boiling and belching over of the water from the economizerand eventually, if the water falls in the boiler, the economizer will bepartly emptied. It will take considerable time to fill the economizerduring which time no Water could enter the boiler, this possiblyresulting in a dangerously low water level therein.

In the case of my series boiler the economizer portion is at all timessteaming where it joins the steam forming portion. If the flow of thewater through the economizer section is freer than it should be therewill be a belching action similar to that in ordinary economizers.

I also find that in this type of boilers it is -of advantage to employvertical tubes, as

there is less tendency of the tubes to warp and bend through the actionof the heat than where the tubes extend horizontally. It is alsoadvantageous to distribute the water retained in the boiler on suddenlyshutting down the boiler, at as many points along the length of theboiler as possible. These features are included in the structure shownwith vertical loops and the distribution of the water at a number ofpoints is also embodied in the structure where the loops are presentedin a generally horizontal position or at an angle to the horizontal.

One important feature of my boiler is that of withdrawing steam andwater to a separating tank or vessel in which the Water is separatedfrom the steam. Where a superheater is used, the steam is thus taken ina comparatively dry state to the superheater. The provision of this tankmakes it possible to carry a much more uniform degree of superheatingand a more uniform pressure than could be obtained without theseparating receptacle.

-The tank also serves a useful purpose where there are impurities in thewater, as the steam, free or practically free from impurities, flowsfrom the separating tank into the superheater, the impurities collectingin the water.

I claim:

1. A drumless boiler including a source of heat, a gas passage, watertubes in said passage connected for progressive flow from the cooler tothe hotter end of said passage, a superheater in said passage nearer thehotter end thereof, some of said tubes forming a superheater in saidpassage nearer the hotter end thereof, some ofsaid tubes forming ascreen for the protection of the superheater, said superheater receivingsteam from the tubes in the hotter end of said passage, means betweenthe superheater and the tubes delineating the location at whichsaturated steam generation ceases, and means forcing more water throughthe tubes preceding the superheater than can be evaporated thereby.

3. In a steam boiler, a gas flue, tubes disposed in said flue andconnected for continuous progressive fluid flow thercthrough from oneend to the other countercurrent to the flow of gases through said flue,means causing water andsteam to be discharged from the end of said tubesopposite the inlet, a steam and water separator receiving saiddischarge, and a superheater constituted of a similar group of tubes andreceiving steam from said separator and disposed intermediate the endsof the first mentioned tubes yvith respect to location in said flue.

DAVID S. JAOOBUS.

